Add agg_tiles_hash_before_apply, warnings, and validate on patch (#1266)

Implement #1244

mbtiles/src/bin/mbtiles.rs

@@ -66,6 +66,9 @@ enum Commands {
         base_file: PathBuf,
         /// Diff file
         patch_file: PathBuf,
+        /// Force patching operation, ignoring some warnings that otherwise would prevent the operation. Use with caution.
+        #[arg(short, long)]
+        force: bool,
     },
     /// Update metadata to match the content of the file
     #[command(name = "meta-update", alias = "update-meta")]
@@ -156,6 +159,12 @@ pub struct SharedCopyOpts {
     /// Skip generating a global hash for mbtiles validation. By default, `mbtiles` will compute `agg_tiles_hash` metadata value.
     #[arg(long)]
     skip_agg_tiles_hash: bool,
+    /// Force copy operation, ignoring some warnings that otherwise would prevent the operation. Use with caution.
+    #[arg(short, long)]
+    force: bool,
+    /// Perform agg_hash validation on the original and destination files.
+    #[arg(long)]
+    validate: bool,
 }
 
 impl SharedCopyOpts {
@@ -181,6 +190,8 @@ impl SharedCopyOpts {
             zoom_levels: self.zoom_levels,
             bbox: self.bbox,
             skip_agg_tiles_hash: self.skip_agg_tiles_hash,
+            force: self.force,
+            validate: self.validate,
             // Constants
             dst_type: None, // Taken from dst_type_cli
         }
@@ -233,8 +244,9 @@ async fn main_int() -> anyhow::Result<()> {
         Commands::ApplyPatch {
             base_file,
             patch_file,
+            force,
         } => {
-            apply_patch(base_file, patch_file).await?;
+            apply_patch(base_file, patch_file, force).await?;
         }
         Commands::UpdateMetadata { file, update_zoom } => {
             let mbt = Mbtiles::new(file.as_path())?;
@@ -258,7 +270,7 @@ async fn main_int() -> anyhow::Result<()> {
                 }
             });
             let mbt = Mbtiles::new(file.as_path())?;
-            mbt.validate(integrity_check, agg_hash).await?;
+            mbt.open_and_validate(integrity_check, agg_hash).await?;
         }
         Commands::Summary { file } => {
             let mbt = Mbtiles::new(file.as_path())?;
@@ -597,6 +609,7 @@ mod tests {
                 command: ApplyPatch {
                     base_file: PathBuf::from("src_file"),
                     patch_file: PathBuf::from("diff_file"),
+                    force: false,
                 }
             }
         );

mbtiles/src/copier.rs

@@ -3,21 +3,24 @@ use std::path::PathBuf;
 
 use enum_display::EnumDisplay;
 use itertools::Itertools as _;
-use log::{debug, info, trace};
+use log::{debug, info, trace, warn};
 use martin_tile_utils::{bbox_to_xyz, MAX_ZOOM};
 use serde::{Deserialize, Serialize};
 use sqlite_hashes::rusqlite::Connection;
-use sqlx::{query, Executor as _, Row, SqliteConnection};
+use sqlx::{query, Connection as _, Executor as _, Row, SqliteConnection};
 use tilejson::Bounds;
 
 use crate::errors::MbtResult;
+use crate::mbtiles::PatchFileInfo;
 use crate::queries::{
     create_tiles_with_hash_view, detach_db, init_mbtiles_schema, is_empty_database,
 };
+use crate::AggHashType::Verify;
+use crate::IntegrityCheckType::Quick;
 use crate::MbtType::{Flat, FlatWithHash, Normalized};
 use crate::{
     invert_y_value, reset_db_settings, CopyType, MbtError, MbtType, MbtTypeCli, Mbtiles,
-    AGG_TILES_HASH, AGG_TILES_HASH_AFTER_APPLY,
+    AGG_TILES_HASH, AGG_TILES_HASH_AFTER_APPLY, AGG_TILES_HASH_BEFORE_APPLY,
 };
 
 #[derive(Debug, Clone, Copy, PartialEq, Eq, Serialize, Deserialize, EnumDisplay)]
@@ -68,12 +71,16 @@ pub struct MbtilesCopier {
     pub apply_patch: Option<PathBuf>,
     /// Skip generating a global hash for mbtiles validation. By default, `mbtiles` will compute `agg_tiles_hash` metadata value.
     pub skip_agg_tiles_hash: bool,
+    /// Ignore some warnings and continue with the copying operation
+    pub force: bool,
+    /// Perform `agg_hash` validation on the original and destination files.
+    pub validate: bool,
 }
 
 #[derive(Clone, Debug)]
 struct MbtileCopierInt {
-    src_mbtiles: Mbtiles,
+    src_mbt: Mbtiles,
-    dst_mbtiles: Mbtiles,
+    dst_mbt: Mbtiles,
     options: MbtilesCopier,
 }
 
@@ -114,23 +121,30 @@ impl MbtileCopierInt {
         }
 
         Ok(MbtileCopierInt {
-            src_mbtiles: Mbtiles::new(&options.src_file)?,
+            src_mbt: Mbtiles::new(&options.src_file)?,
-            dst_mbtiles: Mbtiles::new(&options.dst_file)?,
+            dst_mbt: Mbtiles::new(&options.dst_file)?,
             options,
         })
     }
 
     pub async fn run(self) -> MbtResult<SqliteConnection> {
-        if self.options.diff_with_file.is_none() && self.options.apply_patch.is_none() {
+        if let Some(diff_file) = &self.options.diff_with_file {
-            self.run_simple().await
+            let mbt = Mbtiles::new(diff_file)?;
+            self.run_with_diff(mbt).await
+        } else if let Some(patch_file) = &self.options.apply_patch {
+            let mbt = Mbtiles::new(patch_file)?;
+            self.run_with_patch(mbt).await
         } else {
-            self.run_with_diff_or_patch().await
+            self.run_simple().await
         }
     }
 
-    pub async fn run_simple(self) -> MbtResult<SqliteConnection> {
+    async fn run_simple(self) -> MbtResult<SqliteConnection> {
-        let src_type = self.src_mbtiles.open_and_detect_type().await?;
+        let mut conn = self.src_mbt.open_readonly().await?;
-        let mut conn = self.dst_mbtiles.open_or_new().await?;
+        let src_type = self.src_mbt.detect_type(&mut conn).await?;
+        conn.close().await?;
+
+        conn = self.dst_mbt.open_or_new().await?;
         let is_empty_db = is_empty_database(&mut conn).await?;
 
         let on_duplicate = if let Some(on_duplicate) = self.options.on_duplicate {
@@ -141,24 +155,24 @@ impl MbtileCopierInt {
             return Err(MbtError::DestinationFileExists(self.options.dst_file));
         };
 
-        self.src_mbtiles.attach_to(&mut conn, "sourceDb").await?;
+        self.src_mbt.attach_to(&mut conn, "sourceDb").await?;
 
         let dst_type = if is_empty_db {
             self.options.dst_type().unwrap_or(src_type)
         } else {
-            self.validate_dst_type(self.dst_mbtiles.detect_type(&mut conn).await?)?
+            self.validate_dst_type(self.dst_mbt.detect_type(&mut conn).await?)?
         };
 
         info!(
             "Copying {src_mbt} ({src_type}) {what}to a {is_new} file {dst_mbt} ({dst_type})",
-            src_mbt = self.src_mbtiles,
+            src_mbt = self.src_mbt,
             what = self.copy_text(),
             is_new = if is_empty_db { "new" } else { "existing" },
-            dst_mbt = self.dst_mbtiles,
+            dst_mbt = self.dst_mbt,
         );
 
         if is_empty_db {
-            self.init_new_schema(&mut conn, src_type, dst_type).await?;
+            self.init_schema(&mut conn, src_type, dst_type).await?;
         }
 
         self.copy_with_rusqlite(
@@ -166,12 +180,11 @@ impl MbtileCopierInt {
             on_duplicate,
             dst_type,
             get_select_from(src_type, dst_type),
-            false,
         )
         .await?;
 
         if self.options.copy.copy_tiles() && !self.options.skip_agg_tiles_hash {
-            self.dst_mbtiles.update_agg_tiles_hash(&mut conn).await?;
+            self.dst_mbt.update_agg_tiles_hash(&mut conn).await?;
         }
 
         detach_db(&mut conn, "sourceDb").await?;
@@ -179,62 +192,149 @@ impl MbtileCopierInt {
         Ok(conn)
     }
 
-    pub async fn run_with_diff_or_patch(self) -> MbtResult<SqliteConnection> {
+    /// Compare two files, and write their difference to the diff file
-        let ((Some(dif_file), None) | (None, Some(dif_file))) =
+    async fn run_with_diff(self, dif_mbt: Mbtiles) -> MbtResult<SqliteConnection> {
-            (&self.options.diff_with_file, &self.options.apply_patch)
+        let mut dif_conn = dif_mbt.open_readonly().await?;
-        else {
+        let dif_info = dif_mbt.examine_diff(&mut dif_conn).await?;
-            unreachable!()
+        dif_mbt.assert_hashes(&dif_info, self.options.force)?;
-        };
+        dif_conn.close().await?;
-        let dif_mbt = Mbtiles::new(dif_file)?;
-        let dif_type = dif_mbt.open_and_detect_type().await?;
-        let is_creating_diff = self.options.diff_with_file.is_some();
 
-        let src_type = self.src_mbtiles.open_and_detect_type().await?;
+        let src_info = self.validate_src_file().await?;
 
-        let mut conn = self.dst_mbtiles.open_or_new().await?;
+        let mut conn = self.dst_mbt.open_or_new().await?;
         if !is_empty_database(&mut conn).await? {
             return Err(MbtError::NonEmptyTargetFile(self.options.dst_file));
         }
 
-        self.src_mbtiles.attach_to(&mut conn, "sourceDb").await?;
+        self.src_mbt.attach_to(&mut conn, "sourceDb").await?;
         dif_mbt.attach_to(&mut conn, "diffDb").await?;
 
-        let what = self.copy_text();
+        let dst_type = self.options.dst_type().unwrap_or(src_info.mbt_type);
-        let src_path = &self.src_mbtiles.filepath();
+        info!(
-        let dst_path = &self.dst_mbtiles.filepath();
+            "Comparing {src_mbt} ({src_type}) and {dif_path} ({dif_type}) {what}into a new file {dst_path} ({dst_type})",
-        let dif_path = dif_mbt.filepath();
+            src_mbt = self.src_mbt,
-        let dst_type = self.options.dst_type().unwrap_or(src_type);
+            src_type = src_info.mbt_type,
-        if is_creating_diff {
+            dif_path = dif_mbt.filepath(),
-            info!("Comparing {src_path} ({src_type}) and {dif_path} ({dif_type}) {what}into a new file {dst_path} ({dst_type})");
+            dif_type = dif_info.mbt_type,
-        } else {
+            what = self.copy_text(),
-            info!("Applying patch from {dif_path} ({dif_type}) to {src_path} ({src_type}) {what}into a new file {dst_path} ({dst_type})");
+            dst_path = self.dst_mbt.filepath()
-        }
+        );
-
-        self.init_new_schema(&mut conn, src_type, dst_type).await?;
 
+        self.init_schema(&mut conn, src_info.mbt_type, dst_type)
+            .await?;
         self.copy_with_rusqlite(
             &mut conn,
             CopyDuplicateMode::Override,
             dst_type,
-            &(if is_creating_diff {
+            &get_select_from_with_diff(dif_info.mbt_type, dst_type),
-                get_select_from_with_diff(dif_type, dst_type)
-            } else {
-                get_select_from_apply_patch(src_type, dif_type, dst_type)
-            }),
-            true,
         )
         .await?;
 
+        if let Some(hash) = src_info.agg_tiles_hash {
+            self.dst_mbt
+                .set_metadata_value(&mut conn, AGG_TILES_HASH_BEFORE_APPLY, &hash)
+                .await?;
+        }
+        if let Some(hash) = dif_info.agg_tiles_hash {
+            self.dst_mbt
+                .set_metadata_value(&mut conn, AGG_TILES_HASH_AFTER_APPLY, &hash)
+                .await?;
+        };
+
+        // TODO: perhaps disable all except --copy all when using with diffs, or else is not making much sense
         if self.options.copy.copy_tiles() && !self.options.skip_agg_tiles_hash {
-            self.dst_mbtiles.update_agg_tiles_hash(&mut conn).await?;
+            self.dst_mbt.update_agg_tiles_hash(&mut conn).await?;
+        }
+
+        detach_db(&mut conn, "diffDb").await?;
+        detach_db(&mut conn, "sourceDb").await?;
+        self.validate(&self.dst_mbt, &mut conn).await?;
+
+        Ok(conn)
+    }
+
+    /// Apply a patch file to the source file and write the result to the destination file
+    async fn run_with_patch(self, dif_mbt: Mbtiles) -> MbtResult<SqliteConnection> {
+        let mut dif_conn = dif_mbt.open_readonly().await?;
+        let dif_info = dif_mbt.examine_diff(&mut dif_conn).await?;
+        self.validate(&dif_mbt, &mut dif_conn).await?;
+        dif_mbt.validate_diff_info(&dif_info, self.options.force)?;
+        dif_conn.close().await?;
+
+        let src_type = self.validate_src_file().await?.mbt_type;
+
+        let mut conn = self.dst_mbt.open_or_new().await?;
+        if !is_empty_database(&mut conn).await? {
+            return Err(MbtError::NonEmptyTargetFile(self.options.dst_file));
+        }
+
+        self.src_mbt.attach_to(&mut conn, "sourceDb").await?;
+        dif_mbt.attach_to(&mut conn, "diffDb").await?;
+
+        let dst_type = self.options.dst_type().unwrap_or(src_type);
+        info!("Applying patch from {dif_path} ({dif_type}) to {src_mbt} ({src_type}) {what}into a new file {dst_path} ({dst_type})",
+            dif_path = dif_mbt.filepath(),
+            dif_type = dif_info.mbt_type,
+            src_mbt = self.src_mbt,
+            what = self.copy_text(),
+            dst_path = self.dst_mbt.filepath());
+
+        self.init_schema(&mut conn, src_type, dst_type).await?;
+        self.copy_with_rusqlite(
+            &mut conn,
+            CopyDuplicateMode::Override,
+            dst_type,
+            &get_select_from_apply_patch(src_type, dif_info.mbt_type, dst_type),
+        )
+        .await?;
+
+        // TODO: perhaps disable all except --copy all when using with diffs, or else is not making much sense
+        if self.options.copy.copy_tiles() && !self.options.skip_agg_tiles_hash {
+            self.dst_mbt.update_agg_tiles_hash(&mut conn).await?;
+
+            let new_hash = self.dst_mbt.get_agg_tiles_hash(&mut conn).await?;
+            match (dif_info.agg_tiles_hash_after_apply, new_hash) {
+                (Some(expected), Some(actual)) if expected != actual => {
+                    let err = MbtError::AggHashMismatchAfterApply(
+                        dif_mbt.filepath().to_string(),
+                        expected,
+                        self.dst_mbt.filepath().to_string(),
+                        actual,
+                    );
+                    if !self.options.force {
+                        return Err(err);
+                    }
+                    warn!("{err}");
+                }
+                _ => {}
+            }
         }
 
         detach_db(&mut conn, "diffDb").await?;
         detach_db(&mut conn, "sourceDb").await?;
 
+        self.validate(&self.dst_mbt, &mut conn).await?;
+
         Ok(conn)
     }
 
+    async fn validate(&self, mbt: &Mbtiles, conn: &mut SqliteConnection) -> MbtResult<()> {
+        if self.options.validate {
+            mbt.validate(conn, Quick, Verify).await?;
+        }
+        Ok(())
+    }
+
+    async fn validate_src_file(&self) -> MbtResult<PatchFileInfo> {
+        let mut src_conn = self.src_mbt.open_readonly().await?;
+        let src_info = self.src_mbt.examine_diff(&mut src_conn).await?;
+        self.validate(&self.src_mbt, &mut src_conn).await?;
+        self.src_mbt.assert_hashes(&src_info, self.options.force)?;
+        src_conn.close().await?;
+
+        Ok(src_info)
+    }
+
     fn copy_text(&self) -> &str {
         match self.options.copy {
             CopyType::All => "",
@@ -249,7 +349,6 @@ impl MbtileCopierInt {
         on_duplicate: CopyDuplicateMode,
         dst_type: MbtType,
         select_from: &str,
-        is_diff: bool,
     ) -> Result<(), MbtError> {
         // SAFETY: This must be scoped to make sure the handle is dropped before we continue using conn
         // Make sure not to execute any other queries while the handle is locked
@@ -266,7 +365,7 @@ impl MbtileCopierInt {
         }
 
         if self.options.copy.copy_metadata() {
-            self.copy_metadata(&rusqlite_conn, is_diff, on_duplicate)
+            self.copy_metadata(&rusqlite_conn, on_duplicate)
         } else {
             debug!("Skipping copying metadata");
             Ok(())
@@ -276,38 +375,35 @@ impl MbtileCopierInt {
     fn copy_metadata(
         &self,
         rusqlite_conn: &Connection,
-        is_diff: bool,
         on_duplicate: CopyDuplicateMode,
     ) -> Result<(), MbtError> {
         let on_dupl = on_duplicate.to_sql();
         let sql;
-        if is_diff {
+
         // Insert all rows from diffDb.metadata if they do not exist or are different in sourceDb.metadata.
         // Also insert all names from sourceDb.metadata that do not exist in diffDb.metadata, with their value set to NULL.
-            // Rename agg_tiles_hash to agg_tiles_hash_after_apply because agg_tiles_hash will be auto-added later
+        // Skip agg_tiles_hash because that requires special handling
         if self.options.diff_with_file.is_some() {
             // Include agg_tiles_hash value even if it is the same because we will still need it when applying the diff
             sql = format!(
                 "
     INSERT {on_dupl} INTO metadata (name, value)
-        SELECT IIF(name = '{AGG_TILES_HASH}','{AGG_TILES_HASH_AFTER_APPLY}', name) as name
+        SELECT name, value
-             , value
         FROM (
             SELECT COALESCE(difMD.name, srcMD.name) as name
                  , difMD.value as value
             FROM sourceDb.metadata AS srcMD FULL JOIN diffDb.metadata AS difMD
                  ON srcMD.name = difMD.name
-            WHERE srcMD.value != difMD.value OR srcMD.value ISNULL OR difMD.value ISNULL OR srcMD.name = '{AGG_TILES_HASH}'
+            WHERE srcMD.value != difMD.value OR srcMD.value ISNULL OR difMD.value ISNULL
         ) joinedMD
-        WHERE name != '{AGG_TILES_HASH_AFTER_APPLY}'"
+        WHERE name NOT IN ('{AGG_TILES_HASH}', '{AGG_TILES_HASH_BEFORE_APPLY}', '{AGG_TILES_HASH_AFTER_APPLY}')"
             );
             debug!("Copying metadata, taking into account diff file with {sql}");
-            } else {
+        } else if self.options.apply_patch.is_some() {
             sql = format!(
                 "
     INSERT {on_dupl} INTO metadata (name, value)
-        SELECT IIF(name = '{AGG_TILES_HASH_AFTER_APPLY}','{AGG_TILES_HASH}', name) as name
+        SELECT name, value
-             , value
         FROM (
             SELECT COALESCE(srcMD.name, difMD.name) as name
                  , COALESCE(difMD.value, srcMD.value) as value
@@ -315,10 +411,9 @@ impl MbtileCopierInt {
                  ON srcMD.name = difMD.name
             WHERE difMD.name ISNULL OR difMD.value NOTNULL
         ) joinedMD
-        WHERE name != '{AGG_TILES_HASH}'"
+        WHERE name NOT IN ('{AGG_TILES_HASH}', '{AGG_TILES_HASH_BEFORE_APPLY}', '{AGG_TILES_HASH_AFTER_APPLY}')"
             );
             debug!("Copying metadata, and applying the diff file with {sql}");
-            }
         } else {
             sql = format!(
                 "
@@ -404,7 +499,7 @@ impl MbtileCopierInt {
         Ok(dst_type)
     }
 
-    async fn init_new_schema(
+    async fn init_schema(
         &self,
         conn: &mut SqliteConnection,
         src: MbtType,
@@ -826,6 +921,7 @@ mod tests {
             src_file: src.clone(),
             dst_file: dst.clone(),
             diff_with_file: Some(diff_file.clone()),
+            force: true,
             ..Default::default()
         };
         let mut dst_conn = opt.run().await?;

mbtiles/src/errors.rs

@@ -3,7 +3,7 @@ use std::path::PathBuf;
 use martin_tile_utils::{TileInfo, MAX_ZOOM};
 use sqlite_hashes::rusqlite;
 
-use crate::MbtType;
+use crate::{MbtType, AGG_TILES_HASH, AGG_TILES_HASH_AFTER_APPLY, AGG_TILES_HASH_BEFORE_APPLY};
 
 #[derive(thiserror::Error, Debug)]
 pub enum MbtError {
@@ -77,6 +77,24 @@ pub enum MbtError {
 
     #[error("Invalid zoom value {0}={1}, expecting an integer between 0..{MAX_ZOOM}")]
     InvalidZoomValue(&'static str, String),
+
+    #[error("A file {0} does not have an {AGG_TILES_HASH} metadata entry, probably because it was not created by this tool. Use `--force` to ignore this warning, or run this to update hash value: `mbtiles validate --agg-hash update {0}`")]
+    CannotDiffFileWithoutHash(String),
+
+    #[error("File {0} has {AGG_TILES_HASH_BEFORE_APPLY} or {AGG_TILES_HASH_AFTER_APPLY} metadata entry, indicating it is a patch file which should not be diffed with another file.  Use `--force` to ignore this warning.")]
+    DiffingDiffFile(String),
+
+    #[error("A file {0} does not seem to be a patch diff file because it has no {AGG_TILES_HASH_BEFORE_APPLY} and {AGG_TILES_HASH_AFTER_APPLY} metadata entries.  These entries are automatically created when using `mbtiles diff` and `mbitiles copy --diff-with-file`.  Use `--force` to ignore this warning.")]
+    PatchFileHasNoHashes(String),
+
+    #[error("A file {0} does not have {AGG_TILES_HASH_BEFORE_APPLY} metadata, probably because it was created by an older version of the `mbtiles` tool.  Use `--force` to ignore this warning, but ensure you are applying the patch to the right file.")]
+    PatchFileHasNoBeforeHash(String),
+
+    #[error("The {AGG_TILES_HASH_BEFORE_APPLY}='{1}' in patch file {0} does not match {AGG_TILES_HASH}='{3}' in the file {2}")]
+    AggHashMismatchWithDiff(String, String, String, String),
+
+    #[error("The {AGG_TILES_HASH_AFTER_APPLY}='{1}' in patch file {0} does not match {AGG_TILES_HASH}='{3}' in the file {2} after the patch was applied")]
+    AggHashMismatchAfterApply(String, String, String, String),
 }
 
 pub type MbtResult<T> = Result<T, MbtError>;

mbtiles/src/lib.rs

@@ -32,7 +32,7 @@ pub use update::UpdateZoomType;
 mod validation;
 pub use validation::{
     calc_agg_tiles_hash, AggHashType, IntegrityCheckType, MbtType, AGG_TILES_HASH,
-    AGG_TILES_HASH_AFTER_APPLY,
+    AGG_TILES_HASH_AFTER_APPLY, AGG_TILES_HASH_BEFORE_APPLY,
 };
 
 /// `MBTiles` uses a TMS (Tile Map Service) scheme for its tile coordinates (inverted along the Y axis).

mbtiles/src/mbtiles.rs

@@ -42,6 +42,13 @@ impl CopyType {
     }
 }
 
+pub struct PatchFileInfo {
+    pub mbt_type: MbtType,
+    pub agg_tiles_hash: Option<String>,
+    pub agg_tiles_hash_before_apply: Option<String>,
+    pub agg_tiles_hash_after_apply: Option<String>,
+}
+
 #[derive(Clone, Debug)]
 pub struct Mbtiles {
     filepath: String,
@@ -212,11 +219,6 @@ impl Mbtiles {
             ),
         }
     }
-
-    pub async fn open_and_detect_type(&self) -> MbtResult<MbtType> {
-        let mut conn = self.open_readonly().await?;
-        self.detect_type(&mut conn).await
-    }
 }
 
 pub async fn attach_hash_fn(conn: &mut SqliteConnection) -> MbtResult<()> {

mbtiles/src/patcher.rs

@@ -1,25 +1,53 @@
 use std::path::PathBuf;
 
-use log::{debug, info};
+use log::{debug, info, warn};
-use sqlx::query;
+use sqlx::{query, Connection as _};
 
 use crate::queries::detach_db;
 use crate::MbtType::{Flat, FlatWithHash, Normalized};
-use crate::{MbtResult, MbtType, Mbtiles, AGG_TILES_HASH, AGG_TILES_HASH_AFTER_APPLY};
+use crate::{
+    MbtError, MbtResult, MbtType, Mbtiles, AGG_TILES_HASH, AGG_TILES_HASH_AFTER_APPLY,
+    AGG_TILES_HASH_BEFORE_APPLY,
+};
 
-pub async fn apply_patch(base_file: PathBuf, patch_file: PathBuf) -> MbtResult<()> {
+pub async fn apply_patch(base_file: PathBuf, patch_file: PathBuf, force: bool) -> MbtResult<()> {
     let base_mbt = Mbtiles::new(base_file)?;
     let patch_mbt = Mbtiles::new(patch_file)?;
-    let patch_type = patch_mbt.open_and_detect_type().await?;
+
+    let mut conn = patch_mbt.open_readonly().await?;
+    let patch_info = patch_mbt.examine_diff(&mut conn).await?;
+    patch_mbt.validate_diff_info(&patch_info, force)?;
+    let patch_type = patch_info.mbt_type;
+    conn.close().await?;
 
     let mut conn = base_mbt.open().await?;
-    let base_type = base_mbt.detect_type(&mut conn).await?;
+    let base_info = base_mbt.examine_diff(&mut conn).await?;
+    let base_hash = base_mbt.get_agg_tiles_hash(&mut conn).await?;
+    base_mbt.assert_hashes(&base_info, force)?;
 
-    info!("Applying patch file {patch_mbt} ({patch_type}) to {base_mbt} ({base_type})");
+    match (force, base_hash, patch_info.agg_tiles_hash_before_apply) {
+        (false, Some(base_hash), Some(expected_hash)) if base_hash != expected_hash => {
+            return Err(MbtError::AggHashMismatchWithDiff(
+                patch_mbt.filepath().to_string(),
+                expected_hash,
+                base_mbt.filepath().to_string(),
+                base_hash,
+            ));
+        }
+        (true, Some(base_hash), Some(expected_hash)) if base_hash != expected_hash => {
+            warn!("Aggregate tiles hash mismatch: Patch file expected {expected_hash} but found {base_hash} in {base_mbt} (force mode)");
+        }
+        _ => {}
+    }
+
+    info!(
+        "Applying patch file {patch_mbt} ({patch_type}) to {base_mbt} ({base_type})",
+        base_type = base_info.mbt_type
+    );
 
     patch_mbt.attach_to(&mut conn, "patchDb").await?;
-    let select_from = get_select_from(base_type, patch_type);
+    let select_from = get_select_from(base_info.mbt_type, patch_type);
-    let (main_table, insert1, insert2) = get_insert_sql(base_type, select_from);
+    let (main_table, insert1, insert2) = get_insert_sql(base_info.mbt_type, select_from);
 
     let sql = format!("{insert1} WHERE tile_data NOTNULL");
     query(&sql).execute(&mut conn).await?;
@@ -38,7 +66,7 @@ pub async fn apply_patch(base_file: PathBuf, patch_file: PathBuf) -> MbtResult<(
     );
     query(&sql).execute(&mut conn).await?;
 
-    if base_type.is_normalized() {
+    if base_info.mbt_type.is_normalized() {
         debug!("Removing unused tiles from the images table (normalized schema)");
         let sql = "DELETE FROM images WHERE tile_id NOT IN (SELECT tile_id FROM map)";
         query(sql).execute(&mut conn).await?;
@@ -53,7 +81,7 @@ pub async fn apply_patch(base_file: PathBuf, patch_file: PathBuf) -> MbtResult<(
     SELECT IIF(name = '{AGG_TILES_HASH_AFTER_APPLY}', '{AGG_TILES_HASH}', name) as name,
            value
     FROM patchDb.metadata
-    WHERE name NOTNULL AND name != '{AGG_TILES_HASH}';"
+    WHERE name NOTNULL AND name NOT IN ('{AGG_TILES_HASH}', '{AGG_TILES_HASH_BEFORE_APPLY}');"
     );
     query(&sql).execute(&mut conn).await?;
 
@@ -151,7 +179,7 @@ mod tests {
 
         // Apply patch to the src data in in-memory DB
         let patch_file = PathBuf::from("../tests/fixtures/mbtiles/world_cities_diff.mbtiles");
-        apply_patch(src, patch_file).await?;
+        apply_patch(src, patch_file, true).await?;
 
         // Verify the data is the same as the file the patch was generated from
         Mbtiles::new("../tests/fixtures/mbtiles/world_cities_modified.mbtiles")?
@@ -183,7 +211,7 @@ mod tests {
         // Apply patch to the src data in in-memory DB
         let patch_file =
             PathBuf::from("../tests/fixtures/mbtiles/geography-class-jpg-diff.mbtiles");
-        apply_patch(src, patch_file).await?;
+        apply_patch(src, patch_file, true).await?;
 
         // Verify the data is the same as the file the patch was generated from
         Mbtiles::new("../tests/fixtures/mbtiles/geography-class-jpg-modified.mbtiles")?

mbtiles/src/validation.rs

@@ -7,10 +7,11 @@ use martin_tile_utils::{Format, TileInfo, MAX_ZOOM};
 use serde::Serialize;
 use serde_json::Value;
 use sqlx::sqlite::SqliteRow;
-use sqlx::{query, Row, SqliteExecutor};
+use sqlx::{query, Row, SqliteConnection, SqliteExecutor};
 use tilejson::TileJSON;
 
 use crate::errors::{MbtError, MbtResult};
+use crate::mbtiles::PatchFileInfo;
 use crate::queries::{
     has_tiles_with_hash, is_flat_tables_type, is_flat_with_hash_tables_type,
     is_normalized_tables_type,
@@ -27,6 +28,9 @@ pub const AGG_TILES_HASH: &str = "agg_tiles_hash";
 /// Metadata key for a diff file, describing the eventual [`AGG_TILES_HASH`] value of the resulting tileset once the diff is applied
 pub const AGG_TILES_HASH_AFTER_APPLY: &str = "agg_tiles_hash_after_apply";
 
+/// Metadata key for a diff file, describing the expected [`AGG_TILES_HASH`] value of the tileset to which the diff will be applied.
+pub const AGG_TILES_HASH_BEFORE_APPLY: &str = "agg_tiles_hash_before_apply";
+
 #[derive(Debug, Clone, Copy, Hash, PartialEq, Eq, EnumDisplay, Serialize)]
 #[enum_display(case = "Kebab")]
 pub enum MbtType {
@@ -71,7 +75,7 @@ pub enum AggHashType {
 }
 
 impl Mbtiles {
-    pub async fn validate(
+    pub async fn open_and_validate(
         &self,
         check_type: IntegrityCheckType,
         agg_hash: AggHashType,
@@ -81,12 +85,24 @@ impl Mbtiles {
         } else {
             self.open_readonly().await?
         };
-        self.check_integrity(&mut conn, check_type).await?;
+        self.validate(&mut conn, check_type, agg_hash).await
-        self.check_tiles_type_validity(&mut conn).await?;
+    }
-        self.check_each_tile_hash(&mut conn).await?;
+
+    pub async fn validate<T>(
+        &self,
+        conn: &mut T,
+        check_type: IntegrityCheckType,
+        agg_hash: AggHashType,
+    ) -> MbtResult<String>
+    where
+        for<'e> &'e mut T: SqliteExecutor<'e>,
+    {
+        self.check_integrity(&mut *conn, check_type).await?;
+        self.check_tiles_type_validity(&mut *conn).await?;
+        self.check_each_tile_hash(&mut *conn).await?;
         match agg_hash {
-            AggHashType::Verify => self.check_agg_tiles_hashes(&mut conn).await,
+            AggHashType::Verify => self.check_agg_tiles_hashes(conn).await,
-            AggHashType::Update => self.update_agg_tiles_hash(&mut conn).await,
+            AggHashType::Update => self.update_agg_tiles_hash(conn).await,
             AggHashType::Off => Ok(String::new()),
         }
     }
@@ -453,6 +469,69 @@ LIMIT 1;"
         info!("All tile hashes are valid for {self}");
         Ok(())
     }
+
+    pub async fn examine_diff(&self, conn: &mut SqliteConnection) -> MbtResult<PatchFileInfo> {
+        let info = PatchFileInfo {
+            mbt_type: self.detect_type(&mut *conn).await?,
+            agg_tiles_hash: self.get_agg_tiles_hash(&mut *conn).await?,
+            agg_tiles_hash_before_apply: self
+                .get_metadata_value(&mut *conn, AGG_TILES_HASH_BEFORE_APPLY)
+                .await?,
+            agg_tiles_hash_after_apply: self
+                .get_metadata_value(&mut *conn, AGG_TILES_HASH_AFTER_APPLY)
+                .await?,
+        };
+
+        Ok(info)
+    }
+
+    pub fn assert_hashes(&self, info: &PatchFileInfo, force: bool) -> MbtResult<()> {
+        if info.agg_tiles_hash.is_none() {
+            if !force {
+                return Err(MbtError::CannotDiffFileWithoutHash(
+                    self.filepath().to_string(),
+                ));
+            }
+            warn!("File {self} has no {AGG_TILES_HASH} metadata field, probably because it was created by an older version of the `mbtiles` tool.  Use this command to update the value:\nmbtiles validate --agg-hash update {self}");
+        } else if info.agg_tiles_hash_before_apply.is_some()
+            || info.agg_tiles_hash_after_apply.is_some()
+        {
+            if !force {
+                return Err(MbtError::DiffingDiffFile(self.filepath().to_string()));
+            }
+            warn!("File {self} has {AGG_TILES_HASH_BEFORE_APPLY} or {AGG_TILES_HASH_AFTER_APPLY} metadata field, indicating it is a patch file which should not be diffed with another file.");
+        }
+        Ok(())
+    }
+
+    pub fn validate_diff_info(&self, info: &PatchFileInfo, force: bool) -> MbtResult<()> {
+        match (
+            &info.agg_tiles_hash_before_apply,
+            &info.agg_tiles_hash_after_apply,
+        ) {
+            (Some(before), Some(after)) => {
+                info!(
+                    "The patch file {self} expects to be applied to a tileset with {AGG_TILES_HASH}={before}, and should result in hash {after} after applying",
+                );
+            }
+            (None, Some(_)) => {
+                if !force {
+                    return Err(MbtError::PatchFileHasNoBeforeHash(
+                        self.filepath().to_string(),
+                    ));
+                }
+                warn!(
+                    "The patch file {self} has no {AGG_TILES_HASH_BEFORE_APPLY} metadata field, probably because it was created by an older version of the `mbtiles` tool.");
+            }
+            _ => {
+                if !force {
+                    return Err(MbtError::PatchFileHasNoHashes(self.filepath().to_string()));
+                }
+                warn!("The patch file {self} has no {AGG_TILES_HASH_AFTER_APPLY} metadata field, probably because it was not properly created by the `mbtiles` tool.");
+            }
+        }
+        Ok(())
+    }
 }
 
 /// Compute the hash of the combined tiles in the mbtiles file tiles table/view.

mbtiles/tests/copy.rs

@@ -242,7 +242,7 @@ fn databases() -> Databases {
             copy!(result.path("empty_no_hash", mbt_typ), path(&empty_mbt));
             let dmp = dump(&mut empty_cn).await.unwrap();
             assert_dump!(&dmp, "{typ}__empty");
-            let hash = empty_mbt.validate(Off, Verify).await.unwrap();
+            let hash = empty_mbt.open_and_validate(Off, Verify).await.unwrap();
             allow_duplicates! {
                 assert_snapshot!(hash, @"D41D8CD98F00B204E9800998ECF8427E");
             }
@@ -265,7 +265,7 @@ fn databases() -> Databases {
             copy!(result.path("v1_no_hash", mbt_typ), path(&v1_mbt));
             let dmp = dump(&mut v1_cn).await.unwrap();
             assert_dump!(&dmp, "{typ}__v1");
-            let hash = v1_mbt.validate(Off, Verify).await.unwrap();
+            let hash = v1_mbt.open_and_validate(Off, Verify).await.unwrap();
             allow_duplicates! {
                 assert_snapshot!(hash, @"9ED9178D7025276336C783C2B54D6258");
             }
@@ -276,7 +276,7 @@ fn databases() -> Databases {
                 new_file!(databases, mbt_typ, METADATA_V2, TILES_V2, "{typ}__v2");
             let dmp = dump(&mut v2_cn).await.unwrap();
             assert_dump!(&dmp, "{typ}__v2");
-            let hash = v2_mbt.validate(Off, Verify).await.unwrap();
+            let hash = v2_mbt.open_and_validate(Off, Verify).await.unwrap();
             allow_duplicates! {
                 assert_snapshot!(hash, @"3BCDEE3F52407FF1315629298CB99133");
             }
@@ -291,7 +291,7 @@ fn databases() -> Databases {
             };
             let dmp = dump(&mut dif_cn).await.unwrap();
             assert_dump!(&dmp, "{typ}__dif");
-            let hash = dif_mbt.validate(Off, Verify).await.unwrap();
+            let hash = dif_mbt.open_and_validate(Off, Verify).await.unwrap();
             allow_duplicates! {
                 assert_snapshot!(hash, @"B86122579EDCDD4C51F3910894FCC1A1");
             }
@@ -300,7 +300,7 @@ fn databases() -> Databases {
             // ----------------- v1_clone -----------------
             let (v1_clone_mbt, v1_clone_cn) = open!(databases, "{typ}__v1-clone");
             let dmp = copy_dump!(result.path("v1", mbt_typ), path(&v1_clone_mbt));
-            let hash = v1_clone_mbt.validate(Off, Verify).await.unwrap();
+            let hash = v1_clone_mbt.open_and_validate(Off, Verify).await.unwrap();
             allow_duplicates! {
                 assert_snapshot!(hash, @"9ED9178D7025276336C783C2B54D6258");
             }
@@ -322,7 +322,7 @@ fn databases() -> Databases {
             };
             let dmp = dump(&mut dif_empty_cn).await.unwrap();
             assert_dump!(&dmp, "{typ}__dif_empty");
-            let hash = dif_empty_mbt.validate(Off, Verify).await.unwrap();
+            let hash = dif_empty_mbt.open_and_validate(Off, Verify).await.unwrap();
             allow_duplicates! {
                 assert_snapshot!(hash, @"D41D8CD98F00B204E9800998ECF8427E");
             }
@@ -483,8 +483,8 @@ async fn diff_and_patch(
         eprintln!("TEST: Applying the difference ({b_db} - {a_db} = {dif_db}) to {a_db}, should get {b_db}");
         let (clone_mbt, mut clone_cn) = open!(diff_and_patch, "{prefix}__1");
         copy!(databases.path(a_db, *dst_type), path(&clone_mbt));
-        apply_patch(path(&clone_mbt), path(&dif_mbt)).await?;
+        apply_patch(path(&clone_mbt), path(&dif_mbt), false).await?;
-        let hash = clone_mbt.validate(Off, Verify).await?;
+        let hash = clone_mbt.open_and_validate(Off, Verify).await?;
         assert_eq!(hash, databases.hash(b_db, *dst_type));
         let dmp = dump(&mut clone_cn).await?;
         pretty_assert_eq!(&dmp, expected_b);
@@ -492,8 +492,8 @@ async fn diff_and_patch(
         eprintln!("TEST: Applying the difference ({b_db} - {a_db} = {dif_db}) to {b_db}, should not modify it");
         let (clone_mbt, mut clone_cn) = open!(diff_and_patch, "{prefix}__2");
         copy!(databases.path(b_db, *dst_type), path(&clone_mbt));
-        apply_patch(path(&clone_mbt), path(&dif_mbt)).await?;
+        apply_patch(path(&clone_mbt), path(&dif_mbt), true).await?;
-        let hash = clone_mbt.validate(Off, Verify).await?;
+        let hash = clone_mbt.open_and_validate(Off, Verify).await?;
         assert_eq!(hash, databases.hash(b_db, *dst_type));
         let dmp = dump(&mut clone_cn).await?;
         pretty_assert_eq!(&dmp, expected_b);
@@ -522,10 +522,9 @@ async fn patch_on_copy(
         apply_patch => Some(databases.path("dif", dif_type)),
         dst_type_cli => v2_type,
     };
-    pretty_assert_eq!(
+    let actual = dump(&mut v2_cn).await?;
-        &dump(&mut v2_cn).await?,
+    let expected = databases.dump("v2", v2_type.unwrap_or(v1_type));
-        databases.dump("v2", v2_type.unwrap_or(v1_type))
+    pretty_assert_eq!(&actual, expected);
-    );
 
     Ok(())
 }

mbtiles/tests/snapshots/copy__databases@flat__dif.snap

@@ -12,6 +12,7 @@ CREATE TABLE metadata (
 values = [
     '(  "agg_tiles_hash", "B86122579EDCDD4C51F3910894FCC1A1"  )',
     '(  "agg_tiles_hash_after_apply", "3BCDEE3F52407FF1315629298CB99133"  )',
+    '(  "agg_tiles_hash_before_apply", "9ED9178D7025276336C783C2B54D6258"  )',
     '(  "md-edit", "value - v2"  )',
     '(  "md-new", "value - new"  )',
     '(  "md-remove", NULL  )',

mbtiles/tests/snapshots/copy__databases@flat__dif_empty.snap

@@ -12,6 +12,7 @@ CREATE TABLE metadata (
 values = [
     '(  "agg_tiles_hash", "D41D8CD98F00B204E9800998ECF8427E"  )',
     '(  "agg_tiles_hash_after_apply", "9ED9178D7025276336C783C2B54D6258"  )',
+    '(  "agg_tiles_hash_before_apply", "9ED9178D7025276336C783C2B54D6258"  )',
 ]
 
 [[]]

mbtiles/tests/snapshots/copy__databases@hash__dif.snap

@@ -12,6 +12,7 @@ CREATE TABLE metadata (
 values = [
     '(  "agg_tiles_hash", "B86122579EDCDD4C51F3910894FCC1A1"  )',
     '(  "agg_tiles_hash_after_apply", "3BCDEE3F52407FF1315629298CB99133"  )',
+    '(  "agg_tiles_hash_before_apply", "9ED9178D7025276336C783C2B54D6258"  )',
     '(  "md-edit", "value - v2"  )',
     '(  "md-new", "value - new"  )',
     '(  "md-remove", NULL  )',

mbtiles/tests/snapshots/copy__databases@hash__dif_empty.snap

@@ -12,6 +12,7 @@ CREATE TABLE metadata (
 values = [
     '(  "agg_tiles_hash", "D41D8CD98F00B204E9800998ECF8427E"  )',
     '(  "agg_tiles_hash_after_apply", "9ED9178D7025276336C783C2B54D6258"  )',
+    '(  "agg_tiles_hash_before_apply", "9ED9178D7025276336C783C2B54D6258"  )',
 ]
 
 [[]]

mbtiles/tests/snapshots/copy__databases@norm__dif.snap

@@ -50,6 +50,7 @@ CREATE TABLE metadata (
 values = [
     '(  "agg_tiles_hash", "B86122579EDCDD4C51F3910894FCC1A1"  )',
     '(  "agg_tiles_hash_after_apply", "3BCDEE3F52407FF1315629298CB99133"  )',
+    '(  "agg_tiles_hash_before_apply", "9ED9178D7025276336C783C2B54D6258"  )',
     '(  "md-edit", "value - v2"  )',
     '(  "md-new", "value - new"  )',
     '(  "md-remove", NULL  )',

mbtiles/tests/snapshots/copy__databases@norm__dif_empty.snap

@@ -33,6 +33,7 @@ CREATE TABLE metadata (
 values = [
     '(  "agg_tiles_hash", "D41D8CD98F00B204E9800998ECF8427E"  )',
     '(  "agg_tiles_hash_after_apply", "9ED9178D7025276336C783C2B54D6258"  )',
+    '(  "agg_tiles_hash_before_apply", "9ED9178D7025276336C783C2B54D6258"  )',
 ]
 
 [[]]

tests/expected/mbtiles/meta-all.txt

@@ -109,4 +109,5 @@ json:
       count: 68
       geometry: Point
       layer: cities
+agg_tiles_hash: 84792BF4EE9AEDDC5B1A60E707011FEE